Hi, Daviesjamesp,
Sorry to hear you're experiencing this issue.
Usually, this problem is caused by a corruption in the Windows Hello settings. Renaming the NGC folder using the command prompt should remove all PIN settings and fix the problem.
1-Restart your computer while holding the SHIFT button
2-The Advanced Startup menu will open on the boot.
3-Go to Troubleshoot.
4-Now, go to Advanced Options >Command prompt
5-Run this command to take ownership of the folder:
icacls C:\Windows\ServiceProfiles\LocalService\AppData\Local\Microsoft\Ngc /T /Q /C /RESET
6-Run this command to rename the folder:
Ren C:\Windows\ServiceProfiles\LocalService\AppData\Local\Microsoft\Ngc Ngc.old
7-When finished close the command prompt then click to return to the first screen
8-Click to continue to normal boot
9-Then you should be able to sign in on Windows using your password and configure your PIN again
I hope this information helps. If you have any questions, please let me know and I'll be glad to assist you further.